Pub Date : 2024-07-31DOI: 10.1021/acsestwater.4c00285
Tianwei Mu, Chunzheng Zhang, Manhong Huang, Baokuan Ning, Junxiang Wang
Effective leakage detection is crucial for ensuring operational efficiency, reducing water loss, and maintaining infrastructure integrity in water distribution systems (WDSs). This study presents a specialized leakage detection approach enhanced by spatial–temporal graph convolutional networks (ST-GCN). This method combines large-scale network partition, optimized sensor placement, pilot-scale network partition, and the ST-GCN model, which captures both spatial and temporal dependencies. Then, two case studies are employed to evaluate the effectiveness of this method. The model achieved an average accuracy, precision, recall, and F1-score of 98.38, 98.89, 97.95, and 98.41% across multiple tests for Network A and of 98.51, 98.51, 98.56, and 98.53% for Network B, respectively, which demonstrate the model’s high performance. Furthermore, it compares the model’s simulation results with three existing methods. The enhanced ST-GCN model is superior to those of the other models in terms of accuracy, confirming its superior effectiveness in detecting leakages.
有效的渗漏检测对于确保配水系统（WDS）的运行效率、减少水量损失和维护基础设施完整性至关重要。本研究提出了一种由时空图卷积网络（ST-GCN）增强的专门漏水检测方法。该方法结合了大规模网络分区、优化传感器布置、试验规模网络分区和 ST-GCN 模型，后者可捕捉空间和时间依赖关系。然后，通过两个案例研究来评估该方法的有效性。该模型在多次测试中的平均准确率、精确率、召回率和 F1 分数分别达到了 98.38%、98.89%、97.95% 和 98.41%，在网络 A 和网络 B 中分别达到了 98.51%、98.51%、98.56% 和 98.53%，证明了该模型的高性能。此外，它还将模型的模拟结果与三种现有方法进行了比较。就准确性而言，增强型 ST-GCN 模型优于其他模型，证实了其在检测泄漏方面的卓越功效。
{"title":"Partitioning Leakage Detection in Water Distribution Systems: A Specialized Deep Learning Framework Enhanced by Spatial–Temporal Graph Convolutional Networks","authors":"Tianwei Mu, Chunzheng Zhang, Manhong Huang, Baokuan Ning, Junxiang Wang","doi":"10.1021/acsestwater.4c00285","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00285","url":null,"abstract":"Effective leakage detection is crucial for ensuring operational efficiency, reducing water loss, and maintaining infrastructure integrity in water distribution systems (WDSs). This study presents a specialized leakage detection approach enhanced by spatial–temporal graph convolutional networks (ST-GCN). This method combines large-scale network partition, optimized sensor placement, pilot-scale network partition, and the ST-GCN model, which captures both spatial and temporal dependencies. Then, two case studies are employed to evaluate the effectiveness of this method. The model achieved an average accuracy, precision, recall, and <i>F</i>1-score of 98.38, 98.89, 97.95, and 98.41% across multiple tests for Network A and of 98.51, 98.51, 98.56, and 98.53% for Network B, respectively, which demonstrate the model’s high performance. Furthermore, it compares the model’s simulation results with three existing methods. The enhanced ST-GCN model is superior to those of the other models in terms of accuracy, confirming its superior effectiveness in detecting leakages.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.1021/acsestwater.4c00339
Shengnan Li, Shiyu Zhang, Yun Bai, Xue Li, Shih-Hsin Ho
Nitrogen is a component of many fundamental biomolecules and also participates in environmental redox chemistry. Nitrogen pollution is a serious environmental problem. Biological nitrogen removal is one of the most significant issues in wastewater treatment. Microbial-driven nitrogen transformations are carried out through metabolic pathways. Wastewater treatment systems using microalgal-bacterial cocultures can improve nutrient removal efficiency through interspecies synergistic interactions. However, relevant studies on the nitrogen metabolism and microbial characteristics of microalgal-bacterial systems have not been systematically reviewed and discussed. This Review comprehensively analyzes nitrogen contaminants in various biological nitrogen removal microalgal-bacterial composite systems and summarizes the microbial characteristics and nitrogen-metabolizing enzymes present. Nitrogen metabolism regulation methods involving quorum sensing and genetic regulation are described, and methods of enhancing microbial nitrogen removal through microbial community interactions, enhancing enzyme activity, and promoting electron transfer are introduced in detail. This Review provides a perspective on the improvement and optimization of microalgal-bacterial wastewater treatment technology through analyzing the nitrogen metabolism and increasing process performance.
{"title":"Microalgae Shed Light on Interconnected Nitrogen Transformation in Microalgal-Bacterial Consortia","authors":"Shengnan Li, Shiyu Zhang, Yun Bai, Xue Li, Shih-Hsin Ho","doi":"10.1021/acsestwater.4c00339","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00339","url":null,"abstract":"Nitrogen is a component of many fundamental biomolecules and also participates in environmental redox chemistry. Nitrogen pollution is a serious environmental problem. Biological nitrogen removal is one of the most significant issues in wastewater treatment. Microbial-driven nitrogen transformations are carried out through metabolic pathways. Wastewater treatment systems using microalgal-bacterial cocultures can improve nutrient removal efficiency through interspecies synergistic interactions. However, relevant studies on the nitrogen metabolism and microbial characteristics of microalgal-bacterial systems have not been systematically reviewed and discussed. This Review comprehensively analyzes nitrogen contaminants in various biological nitrogen removal microalgal-bacterial composite systems and summarizes the microbial characteristics and nitrogen-metabolizing enzymes present. Nitrogen metabolism regulation methods involving quorum sensing and genetic regulation are described, and methods of enhancing microbial nitrogen removal through microbial community interactions, enhancing enzyme activity, and promoting electron transfer are introduced in detail. This Review provides a perspective on the improvement and optimization of microalgal-bacterial wastewater treatment technology through analyzing the nitrogen metabolism and increasing process performance.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.1021/acsestwater.4c00338
B. S. K. Kumar, B. Sridevi, V. V. S. S. Sarma, D. Cardinal, Mathieu Sebilo
Nitrate is accumulated in the groundwater, modified through nitrification/denitrification, and exchanged with coastal/estuarine water bodies. To examine the sources and modifications of nitrate, the concentrations and isotopic composition of nitrate (δ 15N and δ 18ONO3) in the groundwater was monitored at 5 locations along the bank of Godavari estuary and in the estuarine waters for 7 months during wet (August–November) and dry (March–May) periods. Though the concentration of nitrate (NO3–) was higher during the wet than dry periods in both the groundwater and estuary, insignificant seasonal variability was observed in δ15N and δ18ONO3 indicating homogenization through mineralization–immobilization turnover of NO3–. The range of δ15N to δ18O of NO3– indicates soil, manure, and septic waste may be the major source of NO3–. The mean ratio of δ15N/δ18O of 1.1 ± 0.3 indicates the occurrence of denitrification in the groundwater. Concentrations δ15NNO3 and δ18ONO3 of NO3– displayed a significant relation between groundwater and estuarine water suggesting that NO3– is possibly denitrified. This study suggests that denitrified NO3– (enriched δ15N and δ18O) reported in the Godavari estuary may be contributed through submarine groundwater discharge than it is hypothesized to flux from the watershed.
{"title":"Isotopic Evidence of Denitrified Nitrate in Groundwater beneath Intensive Agriculture and Exchange with Estuary (Godavari, India)","authors":"B. S. K. Kumar, B. Sridevi, V. V. S. S. Sarma, D. Cardinal, Mathieu Sebilo","doi":"10.1021/acsestwater.4c00338","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00338","url":null,"abstract":"Nitrate is accumulated in the groundwater, modified through nitrification/denitrification, and exchanged with coastal/estuarine water bodies. To examine the sources and modifications of nitrate, the concentrations and isotopic composition of nitrate (δ <sup>15</sup>N and δ <sup>18</sup>O<sub>NO<sub>3</sub></sub>) in the groundwater was monitored at 5 locations along the bank of Godavari estuary and in the estuarine waters for 7 months during wet (August–November) and dry (March–May) periods. Though the concentration of nitrate (NO<sub>3</sub><sup>–</sup>) was higher during the wet than dry periods in both the groundwater and estuary, insignificant seasonal variability was observed in δ<sup>15</sup>N and δ<sup>18</sup>O<sub>NO<sub>3</sub></sub> indicating homogenization through mineralization–immobilization turnover of NO<sub>3</sub><sup>–</sup>. The range of δ<sup>15</sup>N to δ<sup>18</sup>O of NO<sub>3</sub><sup>–</sup> indicates soil, manure, and septic waste may be the major source of NO<sub>3</sub><sup>–</sup>. The mean ratio of δ<sup>15</sup>N/δ<sup>18</sup>O of 1.1 ± 0.3 indicates the occurrence of denitrification in the groundwater. Concentrations δ<sup>15</sup>N<sub>NO<sub>3</sub></sub> and δ<sup>18</sup>O<sub>NO<sub>3</sub></sub> of NO<sub>3</sub><sup>–</sup> displayed a significant relation between groundwater and estuarine water suggesting that NO<sub>3</sub><sup>–</sup> is possibly denitrified. This study suggests that denitrified NO<sub>3</sub><sup>–</sup> (enriched δ<sup>15</sup>N and δ<sup>18</sup>O) reported in the Godavari estuary may be contributed through submarine groundwater discharge than it is hypothesized to flux from the watershed.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1021/acsestwater.4c00442
Jianwang Wu, Mei Lin, Zuliang Chen
Fenton oxidation is highly efficient for removing pollutants from wastewater. However, the low utilization efficiency of oxidants increases operating costs and limits their application in water treatment. To address these issues, this study designed a novel Fenton-like catalyst: zerovalent iron/amorphous manganese composites (ZVI-Mn). This catalyst can activate O2 in situ to generate H2O2 and simultaneously activate H2O2 to produce free radicals, achieving a 96.3% removal efficiency of enrofloxacin (ENR) from water. Radical quenching experiments showed that superoxide radicals (•O2–) (46%) play a dominant role in ENR removal, while hydroxyl radicals (•OH) (28.2%) and singlet oxygen (1O2) (25.8%) also participate. Liquid chromatography–mass spectrometry (LC–MS), density functional theory (DFT) calculations, and toxicity estimations demonstrated effective ENR degradation and significant toxicity reduction of the intermediates, primarily through decarboxylation and ring opening. Additionally, ZVI-Mn achieved a 90.1% removal efficiency of ENR in aquaculture wastewater. This study proposes a new Fenton oxidation technique based on the in situ generation of H2O2, providing a meaningful research basis for environmentally friendly water treatment technologies.
{"title":"In Situ Simultaneous Generation and Activation of Hydrogen Peroxide by the ZVI-Mn Catalyst for the Degradation of Enrofloxacin","authors":"Jianwang Wu, Mei Lin, Zuliang Chen","doi":"10.1021/acsestwater.4c00442","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00442","url":null,"abstract":"Fenton oxidation is highly efficient for removing pollutants from wastewater. However, the low utilization efficiency of oxidants increases operating costs and limits their application in water treatment. To address these issues, this study designed a novel Fenton-like catalyst: zerovalent iron/amorphous manganese composites (ZVI-Mn). This catalyst can activate O<sub>2</sub> in situ to generate H<sub>2</sub>O<sub>2</sub> and simultaneously activate H<sub>2</sub>O<sub>2</sub> to produce free radicals, achieving a 96.3% removal efficiency of enrofloxacin (ENR) from water. Radical quenching experiments showed that superoxide radicals (•O<sup>2–</sup>) (46%) play a dominant role in ENR removal, while hydroxyl radicals (•OH) (28.2%) and singlet oxygen (<sup>1</sup>O<sub>2</sub>) (25.8%) also participate. Liquid chromatography–mass spectrometry (LC–MS), density functional theory (DFT) calculations, and toxicity estimations demonstrated effective ENR degradation and significant toxicity reduction of the intermediates, primarily through decarboxylation and ring opening. Additionally, ZVI-Mn achieved a 90.1% removal efficiency of ENR in aquaculture wastewater. This study proposes a new Fenton oxidation technique based on the in situ generation of H<sub>2</sub>O<sub>2</sub>, providing a meaningful research basis for environmentally friendly water treatment technologies.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Globally intensified lake system degradation has been attributed to high-intensity disturbance and emerged as a significant driver of the declines in lake biodiversity and ecosystem stability. However, potential alterations in feedback mechanisms between aquatic plants and microorganisms after ecological succession are still unclear. This study delves into the influence of aquatic plants on sediment bacterial diversity and nutrient dynamics across different growth phases using Illumina MiSeq sequencing and diffusive gradients in thin film analysis. Our results indicate that the surface temperature of the research area has increased from 20 to 28 °C over the past 25 years, and the dominant species has shifted to Stuckenia pectinata. Constructive species show responsive changes in their organ’s stoichiometric characteristics to adapt to environmental changes. The growth of S. pectinata could affect the diffusion fluxes of NH4+–N, NO3––N, P, and Fe at the sediment–water interface. Morever, the deterministic processes of environmental filtering and competition may have altered the microorganisms in the rhizosphere of S. pectinata, temperature, and water depth were major drivers of seasonal microbial changes. These results in the driver-response relationship of multiple stressors in the lake ecosystem may contribute to the development of engineering projects focusing on restoring aquatic plants.
{"title":"Habitat Disturbance Drives the Feedback of Aquatic Plants on the Microbial Community after Lake Degradation","authors":"Hongwei Yu, Quanlin Lu, Xiaofeng Cao, Yajun Wang, Yan Xu, Guo Yu, Jianfeng Peng, Jing Qi, Chengzhi Hu, Jiuhui Qu","doi":"10.1021/acsestwater.4c00330","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00330","url":null,"abstract":"Globally intensified lake system degradation has been attributed to high-intensity disturbance and emerged as a significant driver of the declines in lake biodiversity and ecosystem stability. However, potential alterations in feedback mechanisms between aquatic plants and microorganisms after ecological succession are still unclear. This study delves into the influence of aquatic plants on sediment bacterial diversity and nutrient dynamics across different growth phases using Illumina MiSeq sequencing and diffusive gradients in thin film analysis. Our results indicate that the surface temperature of the research area has increased from 20 to 28 °C over the past 25 years, and the dominant species has shifted to <i>Stuckenia pectinata</i>. Constructive species show responsive changes in their organ’s stoichiometric characteristics to adapt to environmental changes. The growth of <i>S. pectinata</i> could affect the diffusion fluxes of NH<sub>4</sub><sup>+</sup>–N, NO<sub>3</sub><sup>–</sup>–N, P, and Fe at the sediment–water interface. Morever, the deterministic processes of environmental filtering and competition may have altered the microorganisms in the rhizosphere of <i>S. pectinata</i>, temperature, and water depth were major drivers of seasonal microbial changes. These results in the driver-response relationship of multiple stressors in the lake ecosystem may contribute to the development of engineering projects focusing on restoring aquatic plants.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1021/acsestwater.3c00786
Kathryn G. Lopez, Jinghua Xiao, Christopher Crockett, Christian Lytle, Haley Grubbs, Marc Edwards
Nitrate-induced spallation of lead-bearing solder particles into drinking water is not sufficiently controlled by phosphate-based inhibitors, although adding zinc can improve their performance. Studies using copper coupons coated with new lead–tin solder in water with up to 12 mg/L nitrate demonstrated that zinc orthophosphate reduced lead release by more than 90% and outperformed orthophosphate alone. Lead release and spallation from harvested pipes with decades-old lead–tin solder in a high nitrate water were improved but not eliminated with zinc orthophosphate over a period of months. When applied at a water utility with high source water nitrate, monthly in-home field sampling showed that 90th percentile lead levels dropped below the action level after dosing zinc orthophosphate at full scale for 6 months. Scanning electron microscopy (SEM) analysis of pipe scales revealed that zinc and orthophosphate codeposit at the copper–solder interface and may act as a mixed inhibitor, with zinc inhibiting the cathodic reaction on the copper pipe, phosphate limiting the anodic reaction, and an added benefit of zinc orthophosphate preferentially precipitating at the galvanic interface between the anode and the cathode. Updates to corrosion control guidance for waters with higher nitrate due to seasonal runoff or source water changes are needed.
{"title":"Zinc Orthophosphate Can Reduce Nitrate-Induced Corrosion of Lead Solder","authors":"Kathryn G. Lopez, Jinghua Xiao, Christopher Crockett, Christian Lytle, Haley Grubbs, Marc Edwards","doi":"10.1021/acsestwater.3c00786","DOIUrl":"https://doi.org/10.1021/acsestwater.3c00786","url":null,"abstract":"Nitrate-induced spallation of lead-bearing solder particles into drinking water is not sufficiently controlled by phosphate-based inhibitors, although adding zinc can improve their performance. Studies using copper coupons coated with new lead–tin solder in water with up to 12 mg/L nitrate demonstrated that zinc orthophosphate reduced lead release by more than 90% and outperformed orthophosphate alone. Lead release and spallation from harvested pipes with decades-old lead–tin solder in a high nitrate water were improved but not eliminated with zinc orthophosphate over a period of months. When applied at a water utility with high source water nitrate, monthly in-home field sampling showed that 90th percentile lead levels dropped below the action level after dosing zinc orthophosphate at full scale for 6 months. Scanning electron microscopy (SEM) analysis of pipe scales revealed that zinc and orthophosphate codeposit at the copper–solder interface and may act as a mixed inhibitor, with zinc inhibiting the cathodic reaction on the copper pipe, phosphate limiting the anodic reaction, and an added benefit of zinc orthophosphate preferentially precipitating at the galvanic interface between the anode and the cathode. Updates to corrosion control guidance for waters with higher nitrate due to seasonal runoff or source water changes are needed.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hurricane Hanna brought unprecedented rainfall and flooding to Texas in 2020. Our study evaluated microbial contamination in surface water (SW) and groundwater (GW) across rural communities in Rio Grande Valley (RGV) and Baffin Bay using both culture-based and qPCR methods. Sampling began immediately after the landfall of Hurricane Hanna (August 2020) and until the end of the summer monsoon (August 2021). High concentrations of culturable Escherichia coli and total coliforms were detected during summer monsoon for both surface and GW. E. coli and enterococci were present in all SW samples in RGV. Enterococci was detected in all SW samples collected from BB; however, E. coli was detected in 81% of samples. Like SW, concentration of E. coli and enterococci markers in GW samples were high in RGV. The human-associated fecal marker (HF183) was detected in both SW and GW but mainly in RGV during the dry period. HF183 exhibited a low to moderate correlation with conventional fecal indicators, suggesting the uncertainty of enterococci and E. coli for detection of human fecal pollution. In general, the outcomes of this study serve as foundational data for subsequent investigations aimed at overseeing both established and evolving public health concerns for Texas residents.
{"title":"Microbial Contamination of Surface Water and Groundwater in Flood-Impacted Rural Communities in South Texas Following Hurricane Hanna","authors":"Arash Jafarzadeh, Sina Vedadi Moghadam, Dipti Anik Dhar, Dorina Murgulet, Vikram Kapoor","doi":"10.1021/acsestwater.4c00143","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00143","url":null,"abstract":"Hurricane Hanna brought unprecedented rainfall and flooding to Texas in 2020. Our study evaluated microbial contamination in surface water (SW) and groundwater (GW) across rural communities in Rio Grande Valley (RGV) and Baffin Bay using both culture-based and qPCR methods. Sampling began immediately after the landfall of Hurricane Hanna (August 2020) and until the end of the summer monsoon (August 2021). High concentrations of culturable <i>Escherichia coli</i> and total coliforms were detected during summer monsoon for both surface and GW. <i>E. coli</i> and enterococci were present in all SW samples in RGV. Enterococci was detected in all SW samples collected from BB; however, <i>E. coli</i> was detected in 81% of samples. Like SW, concentration of <i>E. coli</i> and enterococci markers in GW samples were high in RGV. The human-associated fecal marker (HF183) was detected in both SW and GW but mainly in RGV during the dry period. HF183 exhibited a low to moderate correlation with conventional fecal indicators, suggesting the uncertainty of enterococci and <i>E. coli</i> for detection of human fecal pollution. In general, the outcomes of this study serve as foundational data for subsequent investigations aimed at overseeing both established and evolving public health concerns for Texas residents.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-29DOI: 10.1021/acsestwater.4c00087
Terence Zhi Xiang Hong, Kexin Tang, Liming You, Taoqin Chen, Hieu Trung Kieu, Shane Allen Snyder, Kun Zhou
Molecular dynamics (MD) simulations are conducted to assess the Li recovery performance of three zeolitic imidazolate frameworks (ZIFs) employed as selective layers in cation exchange membranes (CEMs) for flow capacitive deionization (FCDI). The three ZIFs (ZIF-8, ZIF-8-Cl, and ZIF-8-Br) share a common metal node (Zn node) but differ in their functional groups on the imidazolate linkers (CH3, Cl, and Br). The performance of the ZIFs is evaluated based on their Li+/Na+ selectivity, determined by calculating the number of Li+ and Na+ ions in the flow-electrode. The adsorption of cations by the ZIFs is also investigated using graphs and contour maps depicting the ZIF–cation interaction energy. Additionally, the simulation results are validated through experiments involving the quantification of cation concentration in the feed solution. The results indicate that Li+/Na+ selectivity depends on the cation affinity of the ZIF. It is preferable to recover Li+ ions from the flow-electrode than from the CEM. Moreover, cations require external energy to enter the pores as they experience repulsion. To achieve high Li+/Na+ selectivity in the flow-electrode, the ZIF selective layers should exhibit a stronger affinity for Na+ than for Li+. Additionally, the cavities at the surface of the ZIFs should be sufficiently small to restrict Na+ entry. Overall, MD simulations are valuable for understanding the mechanisms necessary to achieve high Li+/Na+ selectivity in ZIFs for FCDI applications. Among the three ZIFs tested, ZIF-8-Br exhibits the highest Li+/Na+ selectivity in both simulations and experiments.
本研究进行了分子动力学（MD）模拟，以评估在用于流动电容式去离子（FCDI）的阳离子交换膜（CEM）中用作选择层的三种沸石咪唑框架（ZIF）的锂回收性能。三种 ZIF（ZIF-8、ZIF-8-Cl 和 ZIF-8-Br）具有共同的金属节点（Zn 节点），但咪唑链节上的官能团（CH3、Cl 和 Br）不同。ZIF 的性能是根据其 Li+/Na+ 选择性来评估的，选择性是通过计算流动电极中 Li+ 和 Na+ 离子的数量来确定的。此外，还利用描述 ZIF 与阳离子相互作用能量的图表和等值线图研究了 ZIF 对阳离子的吸附情况。此外，还通过实验对模拟结果进行了验证，实验涉及进料溶液中阳离子浓度的量化。结果表明，Li+/Na+ 选择性取决于 ZIF 的阳离子亲和力。从流动电极中回收 Li+ 离子比从 CEM 中回收更可取。此外，阳离子需要外部能量才能进入孔隙，因为它们会受到排斥。为了在流动电极中实现较高的 Li+/Na+ 选择性，ZIF 选择层对 Na+ 的亲和力应强于对 Li+的亲和力。此外，ZIF 表面的空腔应足够小，以限制 Na+ 进入。总之，MD 模拟对于了解在用于 FCDI 的 ZIF 中实现高 Li+/Na+ 选择性所需的机制非常有价值。在测试的三种 ZIF 中，ZIF-8-Br 在模拟和实验中都表现出了最高的 Li+/Na+ 选择性。
{"title":"Molecular Dynamics Study into Lithium-Ion Recovery from Battery Wastewater Using Flow Capacitive Deionization and a ZIF-8-Coated Cation Exchange Membrane","authors":"Terence Zhi Xiang Hong, Kexin Tang, Liming You, Taoqin Chen, Hieu Trung Kieu, Shane Allen Snyder, Kun Zhou","doi":"10.1021/acsestwater.4c00087","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00087","url":null,"abstract":"Molecular dynamics (MD) simulations are conducted to assess the Li recovery performance of three zeolitic imidazolate frameworks (ZIFs) employed as selective layers in cation exchange membranes (CEMs) for flow capacitive deionization (FCDI). The three ZIFs (ZIF-8, ZIF-8-Cl, and ZIF-8-Br) share a common metal node (Zn node) but differ in their functional groups on the imidazolate linkers (CH<sub>3</sub>, Cl, and Br). The performance of the ZIFs is evaluated based on their Li<sup>+</sup>/Na<sup>+</sup> selectivity, determined by calculating the number of Li<sup>+</sup> and Na<sup>+</sup> ions in the flow-electrode. The adsorption of cations by the ZIFs is also investigated using graphs and contour maps depicting the ZIF–cation interaction energy. Additionally, the simulation results are validated through experiments involving the quantification of cation concentration in the feed solution. The results indicate that Li<sup>+</sup>/Na<sup>+</sup> selectivity depends on the cation affinity of the ZIF. It is preferable to recover Li<sup>+</sup> ions from the flow-electrode than from the CEM. Moreover, cations require external energy to enter the pores as they experience repulsion. To achieve high Li<sup>+</sup>/Na<sup>+</sup> selectivity in the flow-electrode, the ZIF selective layers should exhibit a stronger affinity for Na<sup>+</sup> than for Li<sup>+</sup>. Additionally, the cavities at the surface of the ZIFs should be sufficiently small to restrict Na<sup>+</sup> entry. Overall, MD simulations are valuable for understanding the mechanisms necessary to achieve high Li<sup>+</sup>/Na<sup>+</sup> selectivity in ZIFs for FCDI applications. Among the three ZIFs tested, ZIF-8-Br exhibits the highest Li<sup>+</sup>/Na<sup>+</sup> selectivity in both simulations and experiments.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-29DOI: 10.1021/acsestwater.4c00194
Chamteut Oh, Gang Zheng, Laxmicharan Samineni, Manish Kumar, Thanh H. Nguyen
Accessible and low-cost point-of-use water treatment technology have significant potential to mitigate the risk to public health, particularly in areas with limited resources and in disaster scenarios. Natural cotton fibers functionalized with water-soluble proteins from Moringa oleifera seeds (MO-cotton filter) are a promising technology that exhibits high water permeability and effective removal of various contaminants.. Here, we demonstrated the performance of MO-cotton filters under practically relevant conditions to remove mammalian virus spiked in groundwater. Specifically, MO-cotton filters achieved >3.2-log10 reduction at a superficial velocity of 0.7 m/h of two mammalian viruses, Tulane virus (TV, Caliciviridae, nonenveloped virus) and Transmissible gastroenteritis virus (TGEV, Coronaviridae, enveloped virus), which are representative of a significant portion of waterborne illnesses. We further evaluated the risk of virus particles detached due to shear forces by testing their infectivity and found that the viruses accumulated on the MO-cotton filters pose a minimal risk of contaminating the drinking water source. These findings support that the MO-cotton filter can serve as a point-of-use water purification technology, effectively reducing viruses to a safe drinking water level.
{"title":"Effective Removal of Enteric Viruses by Moringa oleifera Seed Extract Functionalized Cotton Filter","authors":"Chamteut Oh, Gang Zheng, Laxmicharan Samineni, Manish Kumar, Thanh H. Nguyen","doi":"10.1021/acsestwater.4c00194","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00194","url":null,"abstract":"Accessible and low-cost point-of-use water treatment technology have significant potential to mitigate the risk to public health, particularly in areas with limited resources and in disaster scenarios. Natural cotton fibers functionalized with water-soluble proteins from <i>Moringa oleifera</i> seeds (<i>MO</i>-cotton filter) are a promising technology that exhibits high water permeability and effective removal of various contaminants.. Here, we demonstrated the performance of <i>MO</i>-cotton filters under practically relevant conditions to remove mammalian virus spiked in groundwater. Specifically, <i>MO</i>-cotton filters achieved >3.2-log<sub>10</sub> reduction at a superficial velocity of 0.7 m/h of two mammalian viruses, Tulane virus (TV, <i>Caliciviridae</i>, nonenveloped virus) and Transmissible gastroenteritis virus (TGEV, <i>Coronaviridae</i>, enveloped virus), which are representative of a significant portion of waterborne illnesses. We further evaluated the risk of virus particles detached due to shear forces by testing their infectivity and found that the viruses accumulated on the <i>MO</i>-cotton filters pose a minimal risk of contaminating the drinking water source. These findings support that the <i>MO</i>-cotton filter can serve as a point-of-use water purification technology, effectively reducing viruses to a safe drinking water level.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-29DOI: 10.1021/acsestwater.4c00155
Zhao Zhang, Zhengkun Tang, Chensi Shen, Juan Zhou, Xiang-Zhou Meng, Fang Li
A novel E-peroxone process with tandem flow-through (TFT) configuration was developed in this work, and its efficacy was verified via the degradation of recalcitrant compounds, i.e., dyes and poly(vinyl alcohol) (PVA). The gas diffusion electrode (GDE) made of carbon fiber was employed as the cathode, while the anode of ruthenium–iridium acted as a dimensionally stable anode (DSA). The system achieved oxygen self-sufficiency through an innovative oxygen transfer mode, avoiding the need for an additional oxygen supply. The electrodes with TFT configuration ensured high utilization efficiency of ozone as the peroxone reaction occurred continuously in two adjacent chambers. H2O2 yield efficiency was compared between single and TFT E-peroxone processes under various conditions, including flow rates, current densities, and pH values. Under optimal H2O2 production conditions, the TFT E-peroxone process could remove 85.5% of dyes and 73.4% of PVA with single-pass, respectively. Electron paramagnetic resonance (EPR) tests and quenching experiments revealed that hydroxyl radicals (•OH) and carbon radicals are the primary active species. Hydroxyl radicals played a major role in the single and TFT E-peroxone processes. This study demonstrates that the TFT E-peroxone process holds great promise as an advanced technology for efficient wastewater treatment.
{"title":"Novel E-Peroxone Process with Tandem Flow-Through Configuration: In Situ O2 Supplement and Efficient Ozone Utilization","authors":"Zhao Zhang, Zhengkun Tang, Chensi Shen, Juan Zhou, Xiang-Zhou Meng, Fang Li","doi":"10.1021/acsestwater.4c00155","DOIUrl":"https://doi.org/10.1021/acsestwater.4c00155","url":null,"abstract":"A novel E-peroxone process with tandem flow-through (TFT) configuration was developed in this work, and its efficacy was verified via the degradation of recalcitrant compounds, i.e., dyes and poly(vinyl alcohol) (PVA). The gas diffusion electrode (GDE) made of carbon fiber was employed as the cathode, while the anode of ruthenium–iridium acted as a dimensionally stable anode (DSA). The system achieved oxygen self-sufficiency through an innovative oxygen transfer mode, avoiding the need for an additional oxygen supply. The electrodes with TFT configuration ensured high utilization efficiency of ozone as the peroxone reaction occurred continuously in two adjacent chambers. H<sub>2</sub>O<sub>2</sub> yield efficiency was compared between single and TFT E-peroxone processes under various conditions, including flow rates, current densities, and pH values. Under optimal H<sub>2</sub>O<sub>2</sub> production conditions, the TFT E-peroxone process could remove 85.5% of dyes and 73.4% of PVA with single-pass, respectively. Electron paramagnetic resonance (EPR) tests and quenching experiments revealed that hydroxyl radicals (<sup>•</sup>OH) and carbon radicals are the primary active species. Hydroxyl radicals played a major role in the single and TFT E-peroxone processes. This study demonstrates that the TFT E-peroxone process holds great promise as an advanced technology for efficient wastewater treatment.","PeriodicalId":7078,"journal":{"name":"ACS Es&t Water","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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